1. Field of the Invention
The present invention is related generally to the field of orthodontics. More particularly, the present invention is related to a method and system for repositioning teeth from an initial tooth arrangement to a final tooth arrangement.
2. Description of the Background Art
Tooth positioners for finishing orthodontic treatment are described by Kesling in the Am. J. Orthod. Oral. Surg. 31:297-304 (1945) and 32:285-293 (1946). The use of silicone positioners for the comprehensive orthodontic realignment of a patient's teeth is described in Warunek et al. (1989) J. Clin. Orthod. 23:694-700. Clear plastic retainers for finishing and maintaining tooth positions are commercially available from Raintree Essix, Inc., New Orleans, La. 70125, and Tru-Tain Plastics, Rochester, Minn. 55902. The manufacture of orthodontic positioners is described in U.S. Pat. Nos. 5,186,623; 5,059,118; 5,055,039; 5,035,613; 4,856,991; 4,798,534; and 4,755,139. The use of two or more vacuum-formed appliances for effecting orthodontic treatment is suggested in Nahoum (1964) N.Y. State D.J. 30:385-390.
Other publications describing the fabrication and use of dental positioners include Kleemann and Janssen (1996) J. Clin. Orthodon. 30:673-680; Cureton (1996) J. Clin. Orthodon. 30:390-395; Chiappone (1980) J. Glin. Orthodon. 14:121-133; Shilliday (1971) Am. J. Orthodontics 59:596-599; Wells (1970) Am. J. Orthodontics 58:351-366; and Cottingham (1969) Am. J. Orthodontics 55:23-31.
Kuroda et al. (1996) Am. J. Orthodontics 110:365-369 describes a method for laser scanning a plaster dental cast to produce a digital image of the cast. See also U.S. Pat. No. 5,605,459.
U.S. Pat. Nos. 5,533,895; 5,474,448; 5,454,717; 5,447,432; 5,431,562; 5,395,238; 5,368,478; and 5,139,419, assigned to Ormco Corporation, describe methods for manipulating digital images of teeth for designing orthodontic appliances.
U.S. Pat. No. 5,011,405 describes a method for digitally imaging a tooth and determining optimum bracket positioning for orthodontic treatment. Laser scanning of a molded tooth to produce a three-dimensional model is described in U.S. Pat. No. 5,338,198. U.S. Pat. No. 5,452,219 describes a method for laser scanning a tooth model and milling a tooth mold. Digital computer manipulation of tooth contours is described in U.S. Pat. Nos. 5,607,305 and 5,587,912. Computerized digital imaging of the jaw is described in U.S. Pat. Nos. 5,342,202 and 5,340,309. Other patents of interest include U.S. Pat. Nos. 5,549,476; 5,382,164; 5,273,429; 4,936,862; 3,860,803; 3,660,900; 5,645,421; 5,055,039; 4,798,534; 4,856,991; 5,035,613; 5,059,118; 5,186,623; and 4,755,139.
Recently, a new system for treating dental malocculsions has become available under the trade name Invisalign™ System. The Invisalign™ System has two components. The first component is called ClinCheck® and allows practitioners to simulate treatment of teeth by observing and modeling two-week stages of tooth movement. Based on the results of the ClinCheck® component, the second component comprises aligners which are thin, clear, plastic removable dental appliances that correspond to each treatment stage of the ClinCheck® simulation. The aligners are manufactured using advanced computer-controlled fabrication systems. Each aligner is worn by the patient for approximately two weeks before it is exchanged for a next stage aligner intended to further reposition the teeth. The Invisalign™ System addresses many of the significant limitations of conventional braces. In particular, the Invisalign™ System aligners are virtually invisible, and are therefore more aesthetically pleasing for the patient. Second, the aligners are generally less painful and uncomfortable than are traditional braces. Additionally, the aligners can be removed to permit conventional oral hygiene, thus being more healthy for the patient's teeth.
A present shortcoming of the Invisalign™ System, however, is that not all malocculsions can be effectively treated using the removable aligners. Certain tooth repositioning steps, such as extrusion, certain rotations, and the like, can be difficult to achieve with the present Invisalign™ System. For those reasons, it would be desirable to provide improved methods and systems for treating dental malocculsions which at least partially retain the benefits and advantages of the removable aligners of the Invisalign™ System.
Information concerning the Invisalign™ System can be found at the website of Align Technology, Inc. (www.invisalign.com). The Invisalign™ System is described in U.S. Pat. No. 5,975,893, the full disclosure of which is incorporated herein by reference. Other aspects of and potential improvements of the Invisalign™ System are described in the following published PCT applications and pending U.S. patent applications, the full disclosures of which are incorporated herein by reference. They are as follows: Method and system for incrementally moving teeth, filed Apr. 23, 1999, Ser. No. 09/298,268, and now U.S. Pat. No. 6,217,325; System and method for releasing tooth positioning appliances, filed Feb. 16, 1999, Ser. No. 09/250,962, and now U.S. Pat. No. 6,183,248; Composite articles and methods for destructive scanning, filed Sep. 25, 2000, Ser. No. 60/235,240; Manipulable dental model system for fabrication of a dental appliance, filed Dec. 3, 1999, Ser. No. 09/454,786, and now U.S. Pat. No. 6,227,851; Attachment devices and methods for a dental appliance, filed Dec. 3, 1999, Ser. No. 09/454,278, and now U.S. Pat. No. 6,309,215; System and method for producing tooth movement, filed Jan. 14, 2000, Ser. No. 09/483,071, and now U.S. Pat. No. 6,299,440; Systems and methods for varying elastic modulus appliances, filed Jul. 14, 2000, Ser. No. 09/616,830, and now U.S. Pat. No. 6,524,101; Embedded features and methods of a dental appliance, filed Jul. 14, 2000, Ser. No. 09/616,222, and now U.S. Pat. No. 6,572,372; Methods and systems for modeling bite registration, filed Apr. 25, 2000, Ser. No. 60/199,485; Modified tooth positioning appliances and methods and systems, filed Sep. 8, 2000, Ser. No. 09/658,340, and now U.S. Pat. No. 6,497,574; Stress indicators for tooth positioning appliances, filed Jun. 30, 2000, Ser. No. 09/608,593, and now U.S. Pat. No. 6,386,864; and Methods and systems for concurrent tooth repositioning and substance delivery, filed Sep. 21, 2000, Ser. No. 09/666,783, and now U.S. Pat. No. 6,607,382.